Treatment of gasoline



1? atented ec.

.loseph d. @lieniceh, cago, lit, assignor to Universal llil Products Company, Chicago, Ill, a corporation of Delaware No ni-awm Application February 29, 1940, Serial No. 321,572

(on. ii-iz) l5 lClaims.

This invention relates to a method for improving the stability of hydrocarbon distillates insofar as color and gum formation are concerned. More particularly the process concerns methods of preventing deterioration of cracked gasolines which may be stored over relatively long periods of time in the presence of air.

The use of inhibitors to prevent the depreciation of olefin-containing hydrocarbon distillates such as cracked gasoline has been practiced.- Such compounds as alkyl-substituted phenols, aminophenols, fractions of wood tar distillate, etc., have been added to cracked asoline in relatively minor quantities, of the order of 0.0010.1% to inhibit the formation of objectionable oxidation products and prevent loss of color and antiknocir properties of said gasolines during storage periods. The use of inhibitors has replaced or supplemented such forms of refining as acidtreating, clay-treating and the like. The result has been a material saving in refining costs as well as the conservation of substantial amounts of gasoline which were formerly lost in the refining steps.

The present invention offers a means of improving the inhibiting properties of gasoline inhibitors and of effecting material savings in the quantities of such material-which may be required adequately to preserve the valuable properties of gasoline In one specific embodiment the present invention comprises a method for treating olefincontaining hydrocarbon distillates such as cracked gasoline to preserve the valuable properties thereof which consists in adding to said distillate a gasoline gum inhibitor together with a relatively minor quantity of hydroxy alkylene diamine.

These compounds have the general structural wherein at and a are integers. A representative compound is l,3-diaminopropanol.

The present class of compounds are used in combination with recognized gasoline gum inrange of 240-280" 0., and others. The compounds of this invention may be added to the gasoline separately or simultaneously with the gum inimproved hibitor, or may be mixed with thegum inhibitor and the mixture added to the gasoline.

The quantity of hydroxyalkylene diamine commonly used in the gasoline is of the order of 0.0001-0.01% by weight thereof, The exact quantity required is a function of the inhibitor with which it is used and of the gasoline as well as the desired stability of the gasoline treated. The compounds of this invention are not of themselves gum inhibitors and the effect observed is not, therefore, the additive effect such as might be expected by the joint use of two gasoline gum inhibitors.

When the present types of compounds are added alone to cracked gasoline in amounts up to approximately 0.1%, little or no increase in the oxygen bomb induction period is to be observed and storage tests indicate that'no protection is obtained for the gasoline under storage conditions. However, when used with'an inhibitor, the induction period with a given quantity of the inhibitor is markedly increased and with the more efiective compounds of this invention, more than equal weight percentages of the inhibitor can be replaced without suilerlng a loss in inhibitor potency. This will be brought out more fully in the example to be given later.

The compounds of this invention are not neces sarily exactly equivalent in their effects and it should be understood that they cannot necessarily be used to replace one another in the composite inhibitor with equal efiects either on a weight or a molal equivalent basis.

The following example is given to illustrate the usefulness and practicability of the process, but should not be construed as limiting it to the exact conditions or compounds given therein.

A Pennsylvania cracked gasoline was treated with a gosline gum inhibitor comprising N-butyl aminophenol in concentrations of 0.01%. The gasoline thus treated had an oxygen bomb induction period of 330 minutes. When0.01% of 1,3- diamino propanol was added to the inhibited gasoline, the induction period was 610 minutes. When the 1,3-diamino propanol was added to the gasoline without gum inhibitor present, the induction period was the same as that of the original uninhibited gasoline, namely minutes.

I claim as my invention:

1. A process for treating olefin-containing hydrocarbon distillate to prevent depreciation thereof which comprises adding to said distillate a gasoline gum inhibitor and an hydroxy alkylene diamine. 2. A process for treating'cracked gasoline to prevent depreciation thereof which ecmprisee adding tosald gasoline a gasoline hitor and a compound'oi the iollo general structure:

H\ on n n wnsr-c-(cnorn l n H 11 wherein a is an integer.

3. A process for treating cracked gasoline to prevent depreciation thereof which comprises adding to said gasoline a gasoline gum inhibitor and a minor quantity of lB-diopropanol.

4. A process for treating cracked gasoline to prevent depreciation thereof which comprises adding thereto a gasoline gum inhibitor and an amount of an hydroxy alkylene diamine within the limits of approximately 0.000l-0.0l% by weight of the gasoline.

5. A process for treating cracked gasoline to prevent depreciation thereof which comprises adding thereto a gasoline gum inhibitor in amounts of approximately (mill-0.1% and an amount of an hydroxy alkylene diamine within the limits of approximately 0.000l-0.0l%, both by weight of the gasoline.

6. A process for treating cracked gasoline to prevent depreciation thereof which comprises adding to said gasoline a gasoline gum inhibitor consisting of an N-substituted-allryl =14" euphenol and an hydroxy alkylene diamine.

'7. A process for treating cracked gasoline to prevent depreciation thereof which comprises adding to said gasoline a gasoline gum inhibitor consisting of a wood tar fraction boiling within the limits of approximately 240-280 C. and an hydroxy alirylene diamine.

8. An inhibitor ior cracked gasoline compris= aaoae'ra matelr, 240-280" C. and an hydroxy alkylene di amine.

12. a composition of matter useful ior inhibitine' the oxidation of unstable organic substances such as olefin-containing hydrocarbon distillates which comprises a mixture of an antioxidant with an hydroxy alirylene diamine.

13. A composition of matter useful for preventing the oxidation of unstable organic sub.- stances which comprises a mixture of an antioxidant with l,3-diamino propanol.

it. In the art of stabilizing oleflnic distillates against deterioration by the addition oi gum inhibitors thereto, the method of increasing the gum inhibiting potency of the inhibitor which comprises incorporating into the olefinic distillate, in addition to the gum inhibitor, a relatively small amount of a hydroxy allrylene diamine.

15. A stabilizing agent suitable for retarding gum formation in oleflnic distillates comprising a phenolic gum inhibitor and an amount of a hydroxy alkylene diamine such as to increase the inhibiting potency oi the phenolic inhibitor.

Josnrrr a crmnrcn 

